A number of different water soluble products derived from acrylonitrile polymers are known in the art. In general, these products are prepared by reaction of amines with acrylonitrile using sulfur or a sulfur compound as catalyst, usually in the presence of water.
U.S. Pat. No. 4,254,250 discloses reaction of an acrylonitrile polymer with an aminating agent which may be 3-dimethylaminopropylamine at 80.degree.-120.degree. C. under nitrogen. The mixture is heated 1-2 hours at the reaction temperature before addition of sulfur or a sulfur compound catalyst. No solvent for the acrylonitrile polymer is used.
U.S. Pat. No. 3,406,139 discloses preparation of vinylimidazoline and vinyltetrahydropyrimidine polymers by reaction of an acrylonitrile polymer with a primary aliphatic diamine, a secondary-primary aliphatic diamine or certain polyamines at 90.degree.-120.degree. C. in the presence of sulfur or a sulfur containing compound. The reaction may be carried out using a solvent for the acrylonitrile polymer but is preferably carried out in a non-solvent for the acrylonitrile polymer. Similar products are prepared in U.S. Pat. No. 4,041,006 in an inert atmosphere.
U.S. Pat. No. 3,647,769 discloses a process for making water soluble products by reacting a slurry of acrylonitrile polymer with water and a primary or secondary mono- or polyamine at 80.degree.-250.degree. C. for 16 or more hours. The products are believed to be N-substituted poly(acrylamides).
The known water soluble products derived from acrylonitrile polymers have been shown to be more effective than alum and other organic reagents in the removal of particulate matter from municipal and industrial waste and sludge.